The present invention relates to an instrument having a working point which is applied to a surface, and more particularly to a manually manipulated instrument wherein there is a preferred orientation of the working point during the instrument's use.
Various instruments having a point which is applied to a surface are available on the market. These instruments include, but are not limited to, writing systems, such as fountain pens, ballpoint pens, as well as correction fluid applicators and the like. The writing instruments, as a general rule, comprise a writing tip or point which extends from the barrel containing the ink supply, the instrument being held in the hand of the user during the writing process. In most of these writing instruments, particularly ballpoint pens, the writing tips are known to function more effectively if retained in a perpendicular position relative to the surface being written on. However, in most instances the writing instrument is not applied vertically during the writing process, but is inclined to the writing surface by the user at an angle which is generally in the vicinity of 60.degree. to the writing surface.
In the case of a ballpoint pen, typically applied to the writing surface at about a 60.degree. angle, the rim surrounding the ball may contact the writing surface and interfere with the smooth operation of the ball. A danger also exists that application at a 60.degree. angle may provide wear to the ball to the extent that the ball becomes loosened.
In view of the above, it has been proposed that the point or ball-carrying portion of the ballpoint pen be oriented such that it extends at an angle to the axis of the writing instrument barrel to compensate for the tilting of the barrel during the writing process. A pen which is typical of this type of instrument is shown and described in U.S. Pat. No. 5,012,663, issued to Robert L. Brown and assigned to the assignee of the present invention.
It has, however, been found that in employing a pen of the type described above, wherein the point is disposed at an angle with the barrel longitudinal axis, orientation of the point is often difficult and may result in a poor quality of writing being produced. If the point is not oriented such that it lies at right angles to the writing surface, the user will have to reorient the writing instrument, or writing will proceed on the rim of the point.
It is, therefore, an object of the present invention to provide a writing instrument wherein the point extends at an angle to the longitudinal axis of the barrel wherein proper orientation of the point to the writing surface is ensured.
Another object of the invention is to provide a writing instrument of the type set forth above which provides proper orientation of the point to the writing surface prior to the start of the writing process.
A further object of the invention is to provide a writing instrument of the type set forth above wherein the proper orientation of the point to a writing surface is retained during the writing process.
Another object of the invention is to provide a writing instrument of the above type wherein the point is rotatable relative to the barrel but remains fixed relative to the barrel during the writing process.
Yet another object of the invention is to provide a writing instrument of the type set forth above which is simple in construction and easily manufactured.